Is it possible to read a ply format file using python code in Blender
Yes and this applies to most/all other formats.

You can:


Call the operator from Python:bpy.ops.import_mesh.ply(filepath="/path/to.ply")
Import the addon module and run the function which is used for importing:See the source code, its not to hard to see how you would call the load function. eg:

from io_mesh_ply import import_ply
import_ply.load_ply("/path/to.ply")